Type 1 diabetes mellitus (T1DM) is associated with multiple co-morbidities, such as hypertension, dyslipidemia, coronary heart disease and osteoporosis. The foundation of these conditions lays in childhood. Exercise is known to have a positive influence on bone mineral density (BMD) and some impact on cardiovascular disease risk factors in healthy children, but little is known about these associations in children with T1DM.